Objectives: Given the necessity for proxy ratings at end of life, we developed the integrated assessment tool for daily activity and symptoms (IDAS) to evaluate patients with advanced cancer. This study aimed to define IDAS and to test its clinical utility by applying it for a large number of patients.Methods: IDAS is defined as sum of positive aspects (e.g. eating) and negative aspects (e.g. pain) of patient’s life. IDAS is scored daily by nurses and is sequentially plotted in a graph that shows a longitudinal change of patient’s condition throughout hospitalization. We applied IDAS for 1924 patients in palliative care unit, categorizing them into short (<7 days), medium (7–31 days) and long (>32 days) term groups according to the length of hospitalization, and 4 subgroups according to IDAS subtypes defined by the average IDAS and positive/negative IDAS scores (type I: Well-controlled, type II: Fairly controlled, type III: Unstable, type IV: Impaired). IDAS scores were compared among short, medium and long-term groups by using analysis of variance (ANOVA). Length of hospitalization was compared among four subgroups according to IDAS subtypes by using ANOVA. The simple and multiple linear regression analysis was used to determine the association between average IDAS scores and length of hospitalization.Results: Average IDAS and positive IDAS scores were the highest in long-term group (3.7 and 3.8), followed by medium-term (2.3 and 2.5) and short-term groups (0.6 and 0.9), whereas negative IDAS scores were highest in long-term group (−0.1), followed by medium-term (−0.2) and short-term (−0.3). Length of hospitalization was significantly different, with the mean for type I (50.1 days), type II (23.7), type III (23.0), and type IV (10.1). The correlation analysis showed a positive correlation between average IDAS scores and length of hospitalization.Conclusions: Our results suggest that IDAS is a clinically feasible tool to daily evaluate both positive and negative aspects of patient’s condition throughout hospitalization. Higher average IDAS score was associated with a longer hospital stay, suggesting that certain time may be necessary to optimize palliative care treatment and control symptoms while disease severity upon admission may affect the duration of hospitalization.